Consolidated Statements of Comprehensive Income (Unaudited) Parenthetical (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Consolidated Statements of Comprehensive Income (Unaudited) Parenthetical [Abstract]
Unrealized net holding gains arising during the period, pre-tax amounts	$ 10,392	$ 3,733	$ 7,741	$ 5,749
Reclassification adjustment for net gains related to securities available for sale included in net income pre-tax amounts	59	63	86	91
Amortization of prior service cost and actuarial gains pre-tax amounts	$ 416	$ 393	$ 831	$ 786

The change in other comprehensive income due to the amortization of the net prior service costs (credit) into net periodic pension costs.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Publisher FASB
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+ Details

- Definition

Pre tax reclassification adjustment for gains or losses realized upon the sale of securities.

+ References

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+ Details

- Definition

Gross appreciation or the gross loss in value of the total of unsold available-for-sale securities during the period being reported (except when designated as a fair value hedge).

+ References

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+ Details